theme fix

terminus-core/src/components/tabHeader.component.scss

@@ -44,11 +44,11 @@ $tabs-height: 36px;
         background: transparent;
         opacity: 0;
 
-        $button-size: 23px;
+        $button-size: 26px;
         width: $button-size;
         height: $button-size;
         border-radius: $button-size / 2;
-        line-height: $button-size * 0.87;
+        line-height: $button-size;
         align-self: center;
         margin-right: 10px;